http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3677555/
The scams you mention are even discussed in the article. Did you read it? Or are you saying that MRIs are like chelation therapy?
As you can see, the linked article concerns treating intracranial cerebrospinal fluid cysts when treating hydrocephalus (and is effective as far as I know). Now: what does this treatment have to do with the cyst presented in the original blog? The purpose of the shunt in your link is to allow venting of cerebrospinal fluid. Is the cb-fluid flow somehow blocked in the case of the autistic brother in the blog or is the cyst located in a place where shunting does not make any sense?
And to your earlier point, that SpringerLink article shows that they've been draining such cysts with shunts since at least as early as 1985, even if they didn't necessarily know what leaving them in place might result in later in life.